Speed-limiting device.



PATENTED JUNE 23, 1908.

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I A. L MQHUGH. SPEED LIMITING DEVICE.

APPLICATION FILED AUG- 9.1905.

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. ANTHONY L. MCHUGH, OF OlNOINNATI/OHIO, ASSIGN OR TO THE BULLOCKELECTRIU MANU- FAOTURING COMPANY, A OORPORATIONFLOF OHIO.

' SPEED-LIMITING nnvicn.

Specification of Letters Patent.

Patented-June 23, 1908.

Application filed August 9, 1905. Serial No. 273,380.

To all whom it may Concern:

Be itknown that I, ANTHONY L. McHUGn, citizen of the United States,residing at Cincinnati, in the county of'Ha-milton and State 5 of Ohio,have invented certain new and useful Improvements in Speed-LimitingDevices, of which the following is a full, clear,

and exact specification. The present invention relates to speedlimitingdevices for rotary machines, and particularly to that class ofspeed-limiting evices which 0. erate automatically, to close an electriccircuit through suitable translating mechanism upon a certainpredetermined speed being exceeded.

. The object of my invention is to provide'a very simple, compact, andinexpensive device of' this character which may be applied with facilityto a shaft or other rotating art 0 of the machine the speed of rotationof w 'ch is to be limited.

My invention comprises, in one of its aspects, the combination with arotatable member, of a spring pressed circuit controllingdevice adaptedto be mounted upon normally stationary support, a latch for holding saiddevice in retracted position, and a weighted, movable member mountedupon the said rotatable member and adapted .30, to engage and trip thelatch;

I The invention will be more fully understood by referring to theaccompanying drawings, in which Figure 1 is a sectional elevation of aportion'of the shaft and housing of a dynamo-' electric machine havingconnected thereto a speed limiting device embodying my invention;- Fig.2 is a transverse section on the 1ine 22 of Fig. 1; and Fig. 3 is a viewsimilar to Fig. 2 with parts removed, showing the movable part of theswitch in its released or closed position.

The housing 1, surrounding the shaft 2, is here shown provided withoutwardly ex- 5 tending bolts 3, which support the casing 4. Thiscasingis provided at its lower part with a pocket 5 in which is mountedthe circuit :closing switch. Secured in the pocket 5 of the casing bymeans of screws 6 is the block 5; 7, which supports the stationarycontacts 8, 8 of the circuit closing switch. The contacts 8, 8 aresuitably insulated from the block 7.

The movable portion 9 of the switch is ad- -justab1y mounted on thespring pressed plunger 10 which is free to slide through the guide orcasing 11' on the upper part of the block 7, and through'a hole in thelower part of the casing 4. A spring 12 is here shown as surrounding theplunger between the guide, or casing 11, and the movable part 9 of theswitch, and thus tends to move the plunger and movable part of theswitch downward. Theupper part of the plunger is provided with a hook orlatch 13 which normally rests upon the stationary member 11 to retainthe movable part of the switch in its retracted position. The lower partof the plunger extends through the casing and forms a push button forresetting the latch and opening the switch.

Mounted upon the end of the shaft or otherwise mounted on a rotatingpart of the machine is the centrifugal device. This centrifugal devicecomprises the spindle 14 and the weight 15. Secured to the endof theshaft 2 is the plate 16 provided with the outwardly extending lugs '17,17 through which the spindle is free to slide. A spring 18 surrounds thespindle 14 and bears against one of the lugs 17 and the adjustable nut19 to restrain the weight against centrifugal action, until after acertain predetermined speed has been reached. The spring 18 is soadjusted that normally at oii'dinary speeds of rotation the lower end ofthe spindle 14 does not contact with the latch 13 as the spindle 14 andweight 15 rotate with the shaft. If, now, the shaft speeds up above aredetermined amount, in a counter clock-wise direc-.

tion, the weight, by centrifugal action, will move the s, indle outwarduntil its outer end strikes anc trips the latch 13 and'releases theplunger 10. plunger the switch is closed by the action of spring 12. Theadjustable nut 19 provides a ready means for adjusting the tension ofthe spring and therefore for adjusting the s eed at which the latch willbe released ant the switch closed. Having thus described my invention,what I claim as new and desire to secure by Letters Patent is 1. Incombination with a rotating member, a switch normally held in aretracted or open position, a latch for holding the switch in theretracted position, a centrifugal device comprising a weighted spindleslidably mounted to move radially in a direction transverse to the axisof the rotating memhen the latch releases the her, a spr ing forrestraining said weighted 5 indie against centrifugal action up to :ipreeterr nined Value, said spindle and switch bein so relatively mountedthat the switch will e operated by the spindle after a certain radial,movement thereof.

2. In combination with a rotating shaft, a, speed limiting devicecomprising a support, two stationary I switch contacts mounted thereon;movable switch contact, :1- plunger hicli-scn'linovable contact iscarried,- a, latehan inally engaging the said support andholdingthe-plunger and movable switch conztact-inretracte'd' position,:i centrifugal device comprising :i'spindlc slidnhle in a directiontransverse tothe axis of the shaft, and.

in it: plane containingthe said latch, a weight oil-said sp1n(lle", ;anda spring nori nnlly restraining said spindle age-inst centrifugalactioni l 3; "l n-coinb'ini'tion with the rotating nieinher of amachine, a casing'inclosing the end thereof, a, switch in the lowerpartoi said casing, the movable part of which being normally held out ofcontact with the stationary parts by d vertically movable plun er, asupport in said casing, a' movable hool: or latch engaging said supportand holding the plunger and movable member of the switch in a retractedposition, and a weighted spring-restrained member in proximity-Wthereto, mounted in lugs on the end-of the shaft'to move in an outwarddirectioninto 3 contact 'Withsnid latch to close thesiyitclr after acertain predetermined speed: has been re :1 ched I lln testimony whereofI affix my signature, in the presence of two Witnesses.

' ANTHONY L. MOHUGH, Witnesses:

L. LOWENBERG, FRIED J. llrNsrJ-Y.

